Electrical connector



Feb. 18, 1969 KUUCK 3,428,938

ELECTRICAL CONNECTOR Filed Dec. 2, 1966 INVENIOR ANDREW KULICK ATTORNEY S United States Patent 3,428,938 ELECTRICAL CONNECTOR Andrew Kulick, Columbus, Ohio, assignor to Ranco Incorporated, Franklin County, Ohio, a corporation of Ohio Filed Dec. 2, 1966, Ser. No. 598,804 U.S. Cl. 339266 Int. Cl. H011 7/08, 13/24, 7/16 4 Claims ABSTRACT OF THE DISCLOSURE The present invention relates to improvements in electrical terminal connectors by which wires can be readily and securely connected with electrical devices, appliances and the like.

A principal object of the present invention is the provision of a new and improved electric terminal connector for effecting electrical connection of wires to electrical devices and which provides a convenient wire receiving opening and guide means by which the end of a wire to be connected with a device may be inserted in a connecting position with a conductor member and then firmly clamped to the conductor member by rotation of a screw or the like to provide a firm and efficient electrical terminal connection.

More particularly, it is an object of the invention to provide an electrical connector comprising a flat terminal bar having two end edges disposed at less than 180 to one another, and a clamp member retained on one flat surface of the terminal bar by a screw extending through the clamp member and threaded in the bar, a clamp member including a clamping surface generally parallel with the flat surface of the bar and having laterally extending flanges which extend along the respective aforementioned end edges of the bar and cooperate with the clamp surface, the bar and the screw to form a guide aperture for receiving and retaining the end section of a wire inserted therein in a position to be firmly clamped between the flat surface of the bar and the clamp surface when the screw is tightened.

Other objects and advantages of the invention will become apparent from the following description of a preferred form thereof, read in conjunction with the accompanying sheets of drawings wherein:

FIG. 1 is a plan view of a terminal structure embodying the invention, a portion therein being shown broken away;

FIG. 2 is a side elevational view of the terminal connector shown in FIG. 1;

FIG. 3 is an end view of the terminal connector shown in FIG. 1;

FIG. 4 is a sectional view taken along line 44 of FIG. 1;

FIG. 5 is a sectional view taken along line 55 of FIG. 2 and showing a Wire connected to the terminal;

FIG. 6 is a sectional view taken along line 6-6 of FIG. 1 and showing a wire clamped to the terminal; and

FIG. 7 is a sectional view taken substantially along line 7-7 of FIG. 5.

Referring to the drawings, the invention is shown embodied in a terminal connector 10 which may be a part of an electrical control device, such as a room thermostat which comprises an electrical switch which is opened and closed in response to temperature changes to control the circuit of a heating apparatus, such as an electrically operated heating system. For sake of brevity, the room thermostat and heating apparatus are not shown. It is to be understood that the invention could be utilized in many other instances wherein it is desirable to effect electrical connection between electric equipment and a wire.

Suffice to say, the terminal connector 10 comprises a flat terminal bar 11 of suitable metal and a part of which may be embedded in an insulator block forming a support or housing for a switch mechanism, not shown. The end of the bar 11 extending from the switch has end edges 13, 14 which are formed at to one another and are connected by an intermediate portion 15 which extends at 45 to the adjoining edges.

A clamp member 16 is disposed on one side of the bar 11 and is formed of a flat metal plate having a V configuration and the diverged end portions thereof are turned at 90 to the plate proper to form flanges 20, 21 which are disposed in planes at 90 to one another. The apex portion of the clamp member 16 is turned downwardly, as viewed in FIG. 2, to form a spacer lug 23 extending from the clamp proper and is adapted to rest on the upper surface of the terminal bar 11 when the flanges 20, 21 extend along the respective edges 13, 14 of the terminal bar, as seen in FIGS. 1 and 5. The lug 23 terminates somewhat short of the plane of the outer edges of the flanges 20, 21, as is clearly shown in FIG. 4.

The clamp member 16 is secured to the terminal bar 11 by a screw 24 which extends through an opening in the clamp and is threaded into an extruded opening 25 formed through the terminal bar.

Preferably, ridges 26, 27, 28 are formed on the underside of the portion 22 of the clamp 16 by dimpling corresponding depressions in the upper side of the clamp member and the ridges extend normal to the flanges 20, 21, and lug 23, respectively.

When the screw 24 is backed out of its threaded opening 25 sufliciently, the clamp member 16 can be separated from the confronting surface of the terminal bar 11 to permit the insertion of a wire W into the aperture between the adjacent end edges of the flanges 20, 21 and extended along one flange or the other, as indicated by W and W1 of FIG. 5, and between the confronting surfaces of the clamp member 16 and the terminal bar 11. Likewise, a wire, indicated at W2, may be inserted in either of the apertures or spaces between the ends of the lug 23 and the adjacent ends of the flanges 20, 21, respectively. The wire W2 could be revolved and inserted in the space between the lug 23 and flange 21. The shank screw 24 maintains the wire adjacent either of the flanges. Then by threading the screw 24 into the opening 25, the head of the screw forces the clamp member 16 toward the terminal bar 11, and the lug 23 engaging the terminal bar forms a pivot about which the flanged end of the clamp is forced against the wire. This action of the clamp member 16 tightly clamps a substantial section of the wire to the terminal bar 11 and the ridges 26, 27 or 28, as the case may be, and one or the other of ridges 26, 27 or 28 tends to bite into the wire and impress a notch therein to form a good mechanical and electrical connection between the clamp strucure and the wire to provide exceptional resistance to withdrawal of the wire by tension placed on the wire.

It will be seen that the flanges 20, 21 cooperate with the respective end edges 13, 14 of the terminal bar to maintain the clamp member 16 in position to receive the end of a wire section although the screw 24 may be backed off somewhat more than necessary to provide for insertion of the wire. This cooperative action of the flanges 20, 21

and the adjacent edges 13, 14 also prevents rotation of the clamp member by the screw 24 as the screw is tightened.

The lug 23 not only causes the clamp member 16 to tilt to a wire clamping position, but also exerts a canting effort on the screw 24 which tends to tilt or cock the screw in the threaded opening 25 thereby setting up friction between the engaging threads of the screw and its opening which provides a resistance to turning of the screw. Thus, the screw is more or less locked in position to clamp the wire to the terminal bar. A wire inserted between the lug 23 and the flanges 20, 21 is gripped by the ridge 28 and by this arrangement two wires may be securely attached to the terminal, one wire as shown at W2 and the other wire as at W or WI.

The clamp member 16 is preferably formed of brass or copper and is relatively soft so that it is deflected or deformed somewhat when the screw 24 is threaded to firmly draw the clamp member to the wire so that a substantial area of the clamp member engages the wire.

It will be seen that a lead wire can be readily and securely connected to the terminal bar 11 merely by inserting an end of the wire into the opening between the adjacent end edges of the flanges 20, 21 and in a direction to extend along one or the other of the flanges 20, 21, depending upon whichever direction is most convenient for insertion of the wire. A wire may also be inserted between the lug 23 and either of the flanges 20, 21. Then, by merely tightening screw 24, the connection is elfected which resists loosening influences, such as vibrations and mechanical shocks, and the connection provides a strong mechanical binding between the wire and terminal bar.

Although but one form of the invention has been described, it is apparent that other forms, modifications, and adaptations thereof can be provided all falling within the scope of the claims which follow.

I claim:

1. An electrical terminal structure comprising a terminal bar, said bar having an end portion including two edges arranged at less than 180 to one another, a clamp member having a surface confronting a surface of said bar adjacent said two edges, said clamp member having two flanges adapted to overlie and extend along said two edges of said bar respectively, said flanges having adjacent end edges spaced from one another to form an aperture for receiving a wire extended between said flanges and between said confronting surfaces of said clamp and said terminal bar, a spacer member between said surfaces and remote from said flanges and forming a pivot about which said clamp member may be tilted to force said clamp member towards said terminal bar, and means to force said clamp member toward said terminal bar about said spacer member to clamp a wire between said confronting surfaces.

2. An electrical terminal structure as defined in claim 1 in which said spacer member comprises a lug on said clamp member adapted to engage said terminal bar and form a pivot about which said clamp member is tilted to move the flanged portion thereof toward said terminal bar.

3. A terminal structure as defined in claim 1 in which said terminal bar has a flat surface confronting said clamp member, said clamp member comprising a plate having a a V configuration with the diverged ends turned to form flanges overlying and extending along said two edges of said bar and the apex portion turned to form a spacer lug engaging said terminal bar, and said mean comprising a screw extending through an opening through said clamp member and located in said member between said flanges and said lug thereof, and said bar having a threaded opening receiving said screw.

4. A terminal structure as defined in claim 3 in which three projections extend from the under surface of said plate and in the direction of said bar, said projections being disposed between said screw receiving opening in said clamp member and said lug and said flanges, respectively.

References Cited 30 UNITED STATES PATENTS 1,820,701 8/1931 Hetherington 339242 X 1,950,635 3/1934 Steinmayer 339248 X 2,304,711 12/1942 Shenton 339266 M 2,973,503 2/1961 Hansen 339269 X 3,191,140 6/1965 Co'ldren 339263 X FOREIGN PATENTS 29,105 1/1922 Denmark. 194,251 2/ 1965 Sweden. 40 97,153 12/ 1922 Switzerland. 345,676 5/ 1960 Switzerland.

MARVIN A. CHAMPION, Primary Examiner.

P. TEITELBAUM, Assistant Examiner.

US. Cl. X.R. 

